<template>
  <el-breadcrumb
    class="app-breadcrumb"
    separator="/"
  >
    <transition-group name="breadcrumb">
      <el-breadcrumb-item
        v-for="( item,index ) in levelList"
        :key="item.path"
      >
        <span
          v-if="item.redirect==='noRedirect'||index === levelList.length-1"
          class="no-redirect"
        >{{ item.meta.title }}</span>
        <a
          v-else
          @click.prevent="handleLink(item)"
        >{{ item.meta.title }}</a>
      </el-breadcrumb-item>
    </transition-group>
  </el-breadcrumb>
</template>

<script>
import * as pathToRegexp from 'path-to-regexp'
import { watch, reactive, toRefs } from 'vue'
import { useRoute, useRouter } from 'vue-router'
export default {
  setup() {
    const route = useRoute()
    const router = useRouter()
    const state = reactive({
      levelList: []
    })

    watch(route, (route) => {
      if (route.path.startsWith('/redirect/')) {
        return
      }
      getBreadcrumb()
    })

    getBreadcrumb()

    function getBreadcrumb() {
      let matched = route.matched.filter(item => item.meta && item.meta.title)
      const first = matched[0]
      console.log(matched)

      if (!isDashboard(first)) {
        matched = [{ path: '/dashboard', meta: { title: 'Dashboard' }}].concat(matched)
      }

      state.levelList = matched.filter(item => item.meta && item.meta.title && item.meta.breadcrumb !== false)
    }

    function isDashboard(route) {
      const name = route && route.name
      if (!name) {
        return false
      }
      return name.trim().toLocaleLowerCase() === 'Dashboard'.toLocaleLowerCase()
    }

    function pathCompile(path) {
      const { params } = route
      var toPath = pathToRegexp.compile(path)
      return toPath(params)
    }

    function handleLink(item) {
      const { redirect, path } = item
      if (redirect) {
        router.push(redirect)
        return
      }
      router.push(pathCompile(path))
    }

    return {
      handleLink,
      ...toRefs(state)
    }
  }
}
</script>

<style lang="scss" scoped>
.app-breadcrumb.el-breadcrumb {
  display: inline-block;
  font-size: 14px;
  line-height: 50px;
  margin-left: 8px;
  .no-redirect {
    color: #000;
    cursor: text;
  }
}
</style>
